OBJ files are used by wavefront's advanced visualizer application to define and store the geometric objects. Backward and forward transmission of geometric data is made possible through OBJ files. Both polygonal geometry like points, lines, texture vertices, faces and free-form geometry (curves and surfaces) are supported by OBJ format. This format does not support animation or information related to light and position of scenes.
GLB is the binary file format representation of 3D models saved in the GL transmission format (glTF). Information about 3D models such as node hierarchy, cameras, materials, animations and meshes in binary format. This binary format stores the glTF asset (JSON, .bin and images) in a binary blob. It also avoids the issue of increase in file size which happens in case of glTF. GLB file format results in compact file sizes, fast loading, complete 3D scene representation, and extensibility for further development. The format uses model/gltf-binary as MIME type.